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Finding the Fourth Proportional to 638.85, 880.29 and 528.69

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Solution

The fourth proportional to 638.85, 880.29 and 528.69 is: 728.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.85 : 880.29 = 528.69 : x
  2. Step 2: Convert to fraction form
    638.85/880.29 = 528.69/x
  3. Step 3: Cross multiply
    638.85x = 880.29 × 528.69
  4. Step 4: Simplify right side
    638.85x = 465,400.52
  5. Step 5: Solve for x
    x = 465,400.52/638.85
  6. Step 6: Final answer
    x = 728.50

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.